The present invention relates to a braking device particularly usable for skates having a shoe composed of at least one quarter articulated to a shell associated with a supporting frame for two or more wheels.
In conventional roller skates, whether constituted by a shoe associated with a support for two pairs of mutually parallel wheels or by a shoe associated with a supporting frame for two or more aligned wheels, there is the problem of braking the wheels to adjust the speed of the skate.
It is known to use adapted blocks or pads, usually made of rubber, which are arranged at the toe or heel region of the shoe; when the user tilts it forwards or backwards, the free end of the blocks or pads interacts with the ground and braking is thus achieved.
However, these solutions are not satisfactory, as they require the user to rotate the shoe, and thus the frame associated therewith, at the toe or heel, and this can cause loss of balance with consequent falls.
U.S. Pat. No. 1,402,010 discloses a roller skate having a band securable on the user's leg above the malleolar region; a rod is connected to the band.
The rod surrounds the leg to the rear and is then curved so as to laterally affect the leg until it is associated at its ends, in the malleolar region, with a lever system articulated to a structure protruding from the wheel supporting frame.
The lever system protrudes to the rear of the frame and is connected to a plate which is shaped approximately complimentary to the curvature of part of an underlying and facing wheel.
This solution is not free from drawbacks: first of all, a relative movement between the band and the leg is produced throughout sports practice, and this does not make its use comfortable due to the continuous rubbing of the band on the leg.
Furthermore, the plate is activated every time the user bends his leg backwards beyond a given angle, with no real and easy possibility of varying this condition.
Since the shape of the leg is different for each user, for the same rod length there is a different braking at different rotation angles.
Furthermore, the rod acts and presses in the malleolar region, and this can cause discomfort or accidental impacts. Finally, the wheel wears out considerably.
U.S. Pat. No. 4,275,895 provides a partial solution to this drawback, and discloses a brake for skates having two pairs of mutually parallel wheels which acts at the rear wheels.
The brake is constituted by a tongue associated with the shoe at the rear; a plate is associated with the tongue in a rearward position and is pivoted at the supporting frame for the shoe.
The plate has, at its free end, a transverse element and a pair of C-shaped elements is formed at its lateral ends. Following a backward rotation imparted to the tongue, the C-shaped elements interact with the rear wheels facing them, so as to interact with the rolling surface thereof.
Even this solution, however, has drawbacks: it is in fact structurally complicated and thus difficult to industrialize. In fact adapted springs are necessary for allowing the tongue to return to the position in which the C-shaped elements do not interact with the wheels, furthermore increasing the structural complexity.
Furthermore, the structural configuration of the brake causes the C-shaped elements to interact with the wheel even upon a minimal backward rotation imparted to the flap and thus even for involuntary movements, and this produces unwanted braking actions and the possible loss of balance or lack of coordination.
Finally, interaction of the C-shaped elements at the rolling surface of the wheels leads to the rapid wear of the wheels and thus to non-optimum rolling which necessarily entails continuous replacement of the wheels.
U.S. Pat. No. 4,300,781 discloses a braking device for skates that comprise pairs of mutually parallel wheels.
A brake is provided, constituted by a plate transversely pivoted at the rear end of the supporting frame for a shoe. Pads are associated with the end of the plate. The pads face the rolling surface of the pair of rear wheels.
The brake is activated by using a cable which is suitable to rotate the plate, in contrast with a spring associated with the support for the pair of front wheels, so as to move the pads into contact with the rolling surface of the pair of rear wheels.
The cable can be activated by means of rings or handles associated with a band arrangeable on the user's legs by virtue of temporary connection means.
However, this solution has considerable drawbacks: first of all, brake activation can lead to possible loss of balance during sports practice, because the user does not assume, with his body, a position suitable to control sudden speed reduction; only the hand of the skater is in fact involved in the brake activation.
Furthermore, as sports practice can occur while wearing trousers, when the rings are pulled the band may slip along the trousers or pull them so that they slide along the leg, hindering the braking action.
Finally, there is a loose cable which, in addition to being a hindrance to the skater, can accidentally catch during skating, especially since coordination of the arm-legs movement places the legs rhythmically laterally outwards.